1. Field of Invention
The invention relates to a fluorescent lamp and a manufacturing method thereof, and in particular, to a cold cathode fluorescent lamp (CCFL) and a manufacturing method thereof.
2. Related Art
The cold cathode fluorescent lamp (CCFL) is a mercury discharge lamp, and electrons inside the lamp impact upon mercury vapor atoms to make the atoms enter excited states after the high-frequency and high-voltage AC power is applied. The excited mercury atoms return to ground states by emitting ultra-violet rays, and the emitted ultra-violet rays again excite the fluorescent body of the CCFL to generate the visible light.
In the early ages, the CCFL containing the mercury is manufactured by directly adding the liquid mercury to the lamp. However, the content of the mercury cannot be finely controlled in this method, and the liquid mercury has the high vapor pressure, which may contaminate the working instrument and environment so as to generate significantly negative influences on the human body. At present, the CCFL containing the mercury is manufactured by providing a lamp tube having a light emitting chamber and a mercury accommodating chamber, disposing a dollop of mercury into the mercury accommodating chamber, heating the mercury accommodating chamber to release the mercury to the light emitting chamber, and then sealing the light emitting chamber and removing the mercury accommodating chamber.
In the conventional manufacturing method, however, the mercury releasing step needs very high heating temperature, and the released amount of the mercury can only reach the maximum of 80%. Thus, the other mercury cannot be reused and has to be thrown away. Thus, the cost is increased, and the product and environment contamination is caused.